System of control



K. A. SIMMON AND S. B. SCHENCK.

SYSTEM OF CONTROL.

APPLICATION FILED SEPI- I5. 1916.

v 1,330,557. Patented Feb. 10,1920. 7

5 SHEETS-SHEET ld! C! ar Ra val 5e Forward WITNESSES: INVENTORS lfar/ A.J/mman ATTCSRNEY K. A. SIMMON AND S.- B. SCHENCK.

SYSTEM OF CONTROL.

APPLICATION FILED SEPI. I5. I916.

1,330,557. Patented Feb. l0, l920.

5 SHEETS-SHEET 2.

ns w [29 Era/17d F 1?" 62 0 and WiTNESSES: INVENTORS i AhORNEY K. A.SIMMON AND s. B.,SCHENCK;

SYSTEM OF CONTROL.

APPLICATION FILED SEN-15,1916.

Patented Feb. 10, 1920.

. m Y m n m u m M R H 4 a m w s OJ T T u v A u f mma H n 5 C S Y 0 M rAmB 0/ 7 a l. \U 1 P MK 5 672 K M W n E, S S E N H. W

UNITED STATES PATENT OFFICE.

PENNSYLVANIA, ASSIGNORS TO WESTINGHOUSE ELECTRIC AND MANUFACTURINGCOMPANY, A CORPORATION OF PENNSYLVANIA,

SYSTEM OF CONTROL.

Specification of Letters Patent. Patented Feb. 10, 1 920.

Application filed September 15, 1916. Serial No. 120,278.

- county of Allegheny and State of Pennsyl- Vania, have invented a newand useful Improvement in Systems of Control, of which the following'isa specification.

Our invention relates to control systems and apparatus fordynamo-electric machines and especially to thecontrol of electricrailway motors and the like.

The object of our invention is to provide various actuating mechanismsfor a controller or other member that is adapted to em- 1 ploy differentportions of its range of travel, for example to govern the forward orreversed operation of a motor, such actuating mechanisms being biased topredetermined positions by fluid pressure or otherwise, and means forutilizing the fluid-pressure effect,

under predetermined conditions, to produce.

the selected movement of the movable member in a step-by-step manner.

Our invention may best be understood by reference'to the accompanyingdrawings,

wherein Figure 1 is a diagrammatic view of a control apparatus forgoverning the main circuits of a system arranged in accordance with ourinvention; Fig. 2 is a diagrammatic view of the auxiliarygo'verningcircuits for manipulating the apparatus that is shown in Fig.1; Fig. 3 and Fig. 8 are diagrammatic views, respectively correspondingto Fig. 1 and Fig. 2, of modifica-- tions of our invention; and Fig. 4to Fig. 7 inclusive, are diagrammatic views serving to illustrate theoperation of certain control apparatus that is'shown in Fig. 3.

Referring to Fig. 1 of the 'drawin the system shown comprises aplurality o suitable supply-circuit conductors] respectively markedTrolley and Ground; an electric motor having an armature A and a fieldwinding F of the well-known series type;. a main-circuit variableresistor R; a line switch LS; and a control drum 1 for govening thecomplete operation of the motor and of the main-circuit resistor.

The control drum 1 embodies a main-circuit controlling portion 2, and anauxiliary or interlocking circuit portion 3 that is connected in circuitas described in connection with Fig. 2. The illustrated control drum isadapted to occupy a normal intermediate or off position, a plurality ofoperative positions a to d, inclusive, when actuated in one directionthat corresponds to forward motor operation, and a plurality of similarpositions as to 65, inclusive, when moved in the opposite direction,from the off position, that corresponds to reversed running of themotor. 1

An actuating mechanism 4 for the control drum 1 comprises a pinionmember 5which is rigidly secured to-one-end of the operating shaft 6 ofthe control drum and is'adapted to normally mesh with the centralportion of a. suitable horizontally-movable rack member 7 having a notchor recess 8 in the center of its upper face, for a purpose to bedescribed;

A plurality of suitable rods or stems 9 and 10are rigidly secured to therespective ends of the rackniember 7 and a plurality of pistons 11 and12 are attached to the outer ends of the rods 9 and 10, respectively, to

operate within suitable cylinders 13 and 14.

A pair of dissimilar valve members 15 and 16 are associated with therespective cylinders 13 and 14 to admit fluid pressure thereto from anysuitable source (not shown) through suitable pipes or passages 17 and18, respectively, in accordance with predetermined conditions to be setforth.

The cylinder 13 also contains a suitable helical spring member 19 thatis located between the outer'face of the piston 11 and the outer end ofthe cylinder 13 to return the piston device to the illustrated positionunder certain subsequently-described conditions. The force exerted bythe sprin 19 is materially less than the normal pressure availablewhereby the spring is easily compressed when fluid-pressure acts uponthe piston device in opposltion thereto,

but the spring will readily overcome the friction of the moving partsand thus return the piston device to the illustrated position when onlyatmospheric pressure opposes the spring. p

The valve member 15'is normally closed to prevent the accessoffluid-pressure to the cylinder 13 and to effect communication thereofwith the atmosphere, whereas the y I other valve member 16 is normallyopen to admit fluid-pressure to the cylinder 14 and thus bias the pistondevice toward the extreme left position thereof, and is adapted tonormally close communication between the ity of suitable the atmosphere.A plural-- actuating coils, respectively marked On and 011', areprovided for the valve members 15 and 16 and are energized in accordancewith the auxiliary governing system of Fig. 2.

The biasin efiect of the fluid-pressure that is normal y present in thecylinder 1a is arrested in a' suitable intermediate position of the rackmember 7 by means of an eleccylinder 14: and

trically-controlled, automatic locking device 20 that normally engagesthe notch or recess 8 of the rack member, The locking device 20comprises a suitable actuating coil .21, which is energized ashereinafter described to actuate a core member 22 to its upper position,wherein a roller 23 that is secured tothe lower end of the core member1s maintained clear of the rack member in opposition to the action of asuitable spring member 24: that is adapted to bias the roller 23 towardthe rack member whenever the actuating coil 21 is deenergized.

The mechanical operation of the actuating mechanism a without regard tothe electrical connections efi'ected thereby may be set forth asfollows: Upon energization of the actuating coils 0n and Giff and theremoval of the locking device 20 from the recess 8, the normalbalanced-pressure con-' ditions 1n the two cylinders 13 and M arereyersed, that is to say, fluid-pressure is admitted to the cylinder 13through the now open valve 15 and is exhausted from the cylinder 14through the now closed valve 16. Consequently, movement of the pistondevice toward the right from the illustrated posltion is produced. Suchmovement may be arrested at any time by merely deenergizing the offactuating coil, whereby balanced high fluid pressure conditions obtainin both cylinders 13 and it, and a positive and reliable stoppage of thepiston device is To effect actuation of the control. drum 1 vin theopposite direction from its interme diate position or, the locldngdevice 20 is raised from the recess 3, through the @1181? gization ofthe actuating coil 21, and movement of the piston device toward the leftfrom the illustrated position is thereby produced,-by reason of thenormal unbalanced fluid-pressure conditions in the, operating cylinders13 and 14:. To arrest such movement at any desired point, theactuating'coil On may be energized, whereby fluid-pressure is admittedto the cylinder 13, and balanced high fluid-pressure conditions existupon the outer faces of the pistons 11 and 12 and thus eifect thedesired stoppage of the actuating mechanism.

To return the piston device to the illustrated position, the ofi' coilis energized, whole the on coil remains deenergized and, therefore, thehelical spring 19 impels the piston device in opposition to the frictionof the moving parts only until the locking device 20 again engages therecess 8 of the rack member 7 Referring now to Fig. 2, the auxiliarygoverning system shown comprises the supply-circuit conductors llrolleyand Ground; a control resistor'29 for supplying suitable low-voltageenergy to the various actuating coils; a master controller MC that isadapted to occupy a plurality of operative positions 3) to t, 1nclus1ve;

switching device that is adapted to occupy a two position positions and1* that respectively correspond to forward and reverse operation of themotor and of the mainacontrol drum 1, for operating in conjunction withthe master controller MC and the interlocking control drum 3- to governthe actuating mechanism t; a relay device 31 having auxiliary contactmembers 32 for aiding the above-mentioned return movement of the pistondevice from a reversed position; a second relay device 33 havingauxiliary contact mcmhere 3% for governing the on actuating coil duringreverse operation of the control drum 1; and an auxiliary resistor 36that l is utilized in connection with the just-mentioned returnoperation of the actuating mechanism 1;

Assuming that thenctuating mechanism 4 occupies the position illustratedin Fig. l

and that it is desired to effect operation of the motor in the forwarddirection, the

master controller MC may be moved to its initial operative position go,whereby a circuit is completed from the trolley through conductors 37and 38, control fingers 39 and 40 which are bridged by contact segment'41 of the master controller, conductor 42 and control resistor 29 tothe negative conductor Ground i A further'circuit is thereupon completedfrom an intermediate low-voltage point as of. the control resistor 29,through conductor i l, the actuating coil of the switch LS, conductor45, contact member 463-@fi of the auxiliary contro l drum 3 andconductor47 to the negative conductor Ground. Upon the closure of theswitch LS, a holding circuit therefor is formed by the bridging of theinterlock 46 by interlock LS-in, in accordance with a familiar practice.

Another circuit is then completed from the contact segment 41 of themaster controller in its position p, through control finger 48,conductor 49, control fingers 50 and 51 which are bridged by a suitablecontact member of the two-position switching device 30 in its positionf, conductor 52, and actuating coil On, interlock LS-in and conductor 55to the negative conductor.

The actuating coils On and Off arethus simultaneously energized, but nofor-- ward movement of the control drum 1 is possible by reason of thefact that the'lockmg device 20 occupies its normal position.

To allow the desired movement of the actuating mechanism 4, a furtherauxiliary clrcuit is completed from the positively-energized conductor37 through a suitable switch 70, the auxiliary resistor 36, con

ductors. 71 and 72, contact member 729 of the master controller in itsposition 9, conductor 7 3, contact member 7 3 0 of the auxiliary controldrum 3 inits oil position, conductor 74- and the actuating coil 21 ofthe locking device 20 to the negative conductor Ground. Thus, thelocking device 20 is withdrawn from the rack notch 8 to allow thedesired movement of the actuating mechanism. In the other positions ofthe master controller, theactuating coil 21 is deenergized but suchdeenergization does not effect the action of the operating device 4,since the roller 23 of the locking device 20 merely rides along theupper surface of the rack member 7.

As the controller drum 1 approaches its initial operative position a,the control finger 60 becomes disengaged from the con-' tact segment-6'1of the interlock drum 3, thereby deenergizing the off actuating coil andeffecting the above-mentioned stoppage of the movement of the actuatingmechanism 4 by reason of the resulting balanced fluid-pressureconditions therein.

As soon as the main control drum2 occupies its position a, a maincircuit (Fig. 1)

is completed from the trolley through the closed switch LS, the armatureA, conductor 75, control fingers 76 and 77 which are bridged by contactsegment 78 of the main control drum 2, conductor 79, field winding F,conductor 80, control fingers 81 and 82 which are bridged by contactsegment 83 of the control drum 2, conductor 84, the entire main-circuitresistor R, conductor 85, control fingers 86 and 87 which are bridged bycontact segment 88 of the control drum, and conductor 89 to the negativeconductor Ground.

To effect further movement of the main control drum in the desireddirection, the master controller MC is actuated to its p0 sition 1',whereby a circuit is completed from the contact segment 41 throughcontrol finger 90, conductor 91, control finger 92, and contactmember 93of the interlock drum 3, and thence through contact segment '61 to theactuating 0011 OH, as previously traced. Such reenergization of the offcoil effects a movement of the'control device 1 to its position b,whereupon the contact between the control fin 'er 92 and the segment 93'is broken and thus the actuating mechanism 4 is'held in its positionthat corresponds to the control device position 7 for the reasonpreviously set forth.

In position b of the main control drum 2 (see Fig. 1) the contactsegment 83 thereof engages control finger 94, whence circuit iscompleted through conductor 95 to an intermediate point of themain-circuit resistor R, thus effecting the short circuit of a portionof'the resistor to accelerate the motor to a predetermined degree.

Furthermani'pulation of the master controller to its remaining positions8 and t effects a step-by-step movement of the main control drum 2 toits positions 0 and d, respectively, whereby the remaining'sections ofthe resistor R are successively short-circuited to connect the motordirectly across thesupply circuit.

Although we have illustrated a simple main control system in connectionwith the operation of our apparatus, it will be understood that thespecific circuit connections employed are immaterial to the presentinvention with the exception that, when the control device 1 is moved inone direction, forward operation of the motor occurs, whereas actuationof the control device in the 'o posite direction from the off position eects reversed operation of the motor, as about to be described indetail. I

'Moreover, the two portions of the main control drum 2 could readily beadapted for accelerating and regenerative operation, respectivel inaccordance with pIlOI practice, or for 0t er purposes, as will beunderstood.

, Assuming that the master controller MC has been returned to its ofi'position and that the .actuating mechanism 4:, consequently, occupiesthe position illustrated in Fig. 1, the reversed operation or the maincontrol device and, therefore, of the motor may be effected by firstactuating the twoposition switching device 30 to its r" position andthen moving the master controller MG to its initial operative positionp. The circuits of the control resistor 29 and of theactuating coil ofthe switch LS are thereby completed in a manner previously set forth andin addition, a, further circuit is established from the contact segment41 of the master controller through control finger-48, conductor 49,control fingers 50 and 53 which are bridged by'contact member 100 in theposition 7-" of the device 30, conductor 5%, the auxiliary contactmember 34t of the relay device33, which at this time occupies its loweror de'energized position, and thence through the actuating coil On, inaccordance with the circuit previously traced. 7

Upon actuation of the master controller to its position 9, a circuit iscompleted from the contact segment .41 through control finger 58 andcontact members of the interlock drum 3, as hereinbefore described, tocontrol finger or the two-position switching device 30, whence circuitis completed through contact member 102 and control finger 103 thereof,conductor 104, the actuating coil of the'relay device 33 and conductors105 and 55 to the negative conductor Ground, thereby causing the relaydevice 33 to O0- cupy its upper or open position to deenergize the oncoil and thus efiect the release of fluid-pressure from the cylinder 13.

in position 9, the circuit of the actuating coil 21 of the lockingdevice 20 is completed in the same manner as that previously set forth,-thereby allowing the reverse movement of the actuating mechanism 4.

Upon the consequent movement of the main control device 1 to itsposition a, the control finger 60 of the interlock drum 3 becomesdisengaged from the contact member 61, thus, deenergizing the relaydevice '33 which drops to its lower position to reenergize thefonactuating coil, and thus arrest the movement or the actuating mech anism4, by reason of the balanced high fluid-pressure conditions therein.

As soon as the main control drum 2 oocupies its position a, the maincircuit (see Fig. 1) is completed through the armature A'in the samedirection as before, conductor 75, control finger 7 6, contaetsegme'nt120, conductor 121, contact segment 122 and control finger 81 of themain control drum, conductor 80, the field winding 1* in the reversedirection from that originally taken,

conductor 79, control. linger 77,- contact segment 123, conductor 124:,contact segment 125 and control finger 82, whence circuit is completedas previousl described.

Further operation of the control drum in the desired direction isaccomplished by moving the master controller to its successive'positions7', s and 15, whereby a step-bystep movement of the control device 1 is'efi'ected in a manner similar to that already set forth.

To effect the return movement of the actuating mechanism fl to theillustrated position, the master controller MG is actuated to its offposition, whereby a circuit is completed from the auxiliary resistor 36through conductor 71, control and 107 which are bridged by contactsegment 108 of the two-position switching device 30 in its position 1",conductor 109, con trol fingers 110 and 111 which are bridged by contactmember 112 of the master controller in its off position, conductor 113,

contact members 32 of the relay device, con-- ductor 116, controlfingers 117 and 118 which are bridged by contact member-119 of theauxiliary drum 3 in any but its off position, conductor 126, the oil'actuating coil, conductor 127 (the line switch LS being open in the 0dposition of the controller MC),-auXiliary contact members 128'of therelay device 31, and conductor 129 to ground. Thus the fluid-pressure isexhausted from sure obtains in both cylinders 13 and 14 of the actuatingmechanism 4. Consequently, the force exerted by the helical spring 19upon the piston'll is suflicient to move the actuating mechanism to theillustrated position, wherein it is locked by the device 20, aspreviously described. I

Reference may now be had to Fig. 3, wherein the system shown comprisesthe supthe cylinder 14, so that atmospheric presply-circuit conductorsTrolley and Ground;

a plurality of dynamo-electric machines respectively having armatures A1and A2, and

field windings F1 and F2 of the series type;

a controlling device 131 of the drum type A that embodies a main-circuitsection 132 and an auxiliary-circuit section 133; a variablemain-circuit resistor R; an actuating mech-. 'anism 134101 the controldevice 131 that corresponds to the previously-described actuatingmechanism a; a locking device 135 that is associated with the actuatingmechanism 13a in a manner to be described; a line switch LS; and a limitswitch 1&7 of a well known type that is provided with auxiliarycircuitcontact members 148.

The actuating mechanism 134.- comprises a pinion 136 which is secured tothe upper iso end of the operating shaft 137 of the controlling device131 and is adapted to mesh with a horizontally movable rack member 138,to the opposite ends of which pistons 139 and 140 are suitably attachedto operate within a relatively long cylinder 141. An opening or aperture142 is provided in the cylinder wall approximately three-quarters of thecylinder length fromthe lefthand end thereof, as shown in the drawing,for a purpose to be set forth. A pair of valve members 143 and 144 thatcorrespond to the previously-described valve members 15 and 16, areassociated with the respective ends of the cylinder 141 to admit fluidpressurethereto under predetermined conditions from a suitable source(not shown) through suitable pipes or passages 145 and 146,respectively.

The locking device 135 comprises a rod or pm 150, that is adapted tonormally effect an air-tight engagement with the cylinder aperture 142,by reason of the biasing action of a spring member 151, that may beinclosed within a suitable incasing member or cylinder 152. A piston 153is adapted to operate within the cylinder 152, in opposition to theaction of the spring 151, when the actuating coil of a valve member 154,which is similar to the valve 144, is energized, thus elevating the pin150 within the aperture 142, for purposes to be described. An interlockboard 156 is movable with the stem of the piston 153 and carries tweenthe cylinder and the atmosphere, it

,follows that the pistons 139 and 140 are biased to their extremeright-hand position, whereby the pinion 136 engages the lefthand end ofthe rack member 138, as shown in the drawing.

The mechanical operation of the actuating mechanism 134 and of thelocking device 135 without regard to the specific electrical connectionseffected thereby, may be briefly described as follows: The off positionof the actuating mechanism when it is desired to effect immediateforward Operation of the control device 131, is illustrated in Fig. 3and in a more simple manner in Fig. 4. Upon energization of theactuating coils On. and Off for the valve members 144 and 143,respectively, the reversal of the normal fluid-pressure conditions inthe cylinder 141 causes the pistons 139 and 140 to move toward the leftfrom the illustrated position, whereby the control device 131successively passes through its sequently described in detail.

forward positions a to f, inclusive, as sub- However, when the controldevice 131 reaches its position the piston 140 strikes the pin 150 ofthe locking device 135 and further forward movement of the control drumis prevented, j

as shown in Fig. 5.

To eifect movement of the control device 131 to its initial reverseposition 0/, the valve member 154 of the locking device 135 is energizedto elevate the pin 150 Within the cylinder aperture 142 to a positionwhere its lower end is substantially flush with the inner cylindersurface, thus permitting the 'piston 140 to pass beyond the aperture,whereupon the pin 15-0 is again lowered within the aperture 142. Thusthe escape of fluid-pressure from the cylinder, or admission offluid-pressure from the valve memelement 00-3; of the control drum isshown,

in each of Figs. 4 to 7, inclusive,'in positions that respectivelycorrespond to the positions a, f, a and f of the control drum.

Referring now to the auxiliary control circuits of Fig. 8, the systemshown comprises the supply-circuit conductors Trolley and Ground; the.auxiliary section 133 of'the control device 131; the actuating coils ofthe switching device LS and of the valve members 143 and 144; theauxiliary contact members 148 of the limit switch 147 variousinterlocking contact members that are associated with the switch LS andwith the locking device 135. as illustrated in Fig. 3; a mastercontroller MC that is adapted to occupy a plurality of positions ;0 tou, inclusive; a two-position switching device 160 that is adapted tooccupy positions f or r", and which corresponds to the previouslydescribed switching device 30; and a control resistor 161 and anauxiliary resistor 162 that respectively correspond to the resistors 29and 36 that were described in connection with Fig. 2. Y

Assuming that the various pieces of control apparatus occupy therespective illustrated positions, acceleration of the motor in theforward direction may be effected by actuating the master controller MCto its initial position 77, whereupon a circuit is completed from theTrolley, through conductor 165, control fingers 166 and 167, which arebridged by contact segment. 16-8 of the master controller; conductorl69'and the control resistor 161 to the negative conductor Ground.

A. further circuit is thereupon completed from a suitably 1ow-voltagepoint 170 of the control" resistor 161, through conductors 171 and 172,the actuating coil-of the switch LS,

interlock135-out when the locking devlce' occupies its illustratedposition, conductors 173 and 174, control fingers 175 and 176, which arebridged by contact segment 177 of the auxiliary control drum 133 in itsposition a only, and conductors 178 and 179 to the negativeconductorGround. Upon the closure of the switch LS, a holding circuit of afamiliar type is formed by the bridging of the conductors 173 and 179,by

an interlock LS-in. v

A further circuit is completed at this time from the positivelyenergized conductor 171 through conductors 180 and 181 and controlfinger 182, to contact segment 183 of the master control, whereby thecontact segment is energized.

.Still another circuit is completed from the conductor 180 throughconductor 184, interlock LSin, the actuating coil On of the valve member144 and conductor 184 to the ductor 190, the entire main-circuitresistor R, conductor 191, armature A1, conductor 192, control fingers193 and 194,'which are bridged by contact segment 195, conductor 196,field winding F1, conductor 197, control fingers 198 and 199, which arebridged by contact segment 200, conductors 201 and 202, control finger203, contact member 204, control finger 205, conductor 206, armature A2,conductor 207 control fingers 208' and 209, which are bridged by contactsegment 210, conductor 211, field winding F2, conductor 212, controlfingers 213 and 214,

which are bridged by contact segment 215, conductors 216 and'2l7, theseries actuating coil of the limit'switch 147, and conductor motors arethus connected in series relation 7 cuit.

218 to the negative conductor Ground. The

with the resistor R across the supply cir- Referring again to Fig. 8,upon actuation of the master controller to its position 9, a circuit isestablished from the contact segment 183 thereof through control finger220,

- conductor 221, control fingers 222 and 223,

which are bridged. by contact segment 224 of the auxiliary control drum133, conduc- .1,sso,557

tor 225, auxiliary contact members 148 of the limit switch 147 in itslower position, conductor 226, the actuating coil .Ofi' of the valvemember 143, and conductor 227 to the negative conductor Ground.

' Since the actuating coils On and Ofl', are, simultaneously energized,movement of the control device 131 to its second operative position 1)occurs, whereupon the circuit of the actuating coil Ofl' is interruptedby the disengagement of the control finger 222 from the contact segment224 of the auxiliary drum. 133, and the control device 131 is thus heldin itsposition b by reason of the balanced fluid-pressure conditions inthe cylinder 141, in accordance with the previousl described operationof the actuating me'c ianism 134. 1

Since the control device occupies its position I) the control finger 228that is connected. to an intermediate point of the maincircuit resistorB (Fig. 3) engages the contact segment 189 of the main control drum 132,whereby a portion of the resistor R is excluded from circuit, inaccordance with familiar practice, to efi'ect a predetermined degree ofacceleration of the motor.

When the master controller MO is moved to its next position 1*, acircuit is completedactuating coils On and Ofl' being thus 7 againenergized simultaneously, movement of the control-device 131 to itsposition 0 ensues, and such movement is arrested in position c-byreasonof the disengagement of the control finger 231 from the contactsegment 224 of the auxiliary drum 133.

In position 0, the contact segment 189 of the maincontrol drum 132engages control finger 232 which is connected to one terminal of themain-circuit resistor R, and thus the remaining Section of the resistoris excluded from circuit, whereby the motors are con- 'nected in fullseries relation.

, Upon actuation of the mastercontroller to its position 8, acircuit isestablished from the contact segment 183 thereof, through control finger233, conductor 234, control finger 235, which engages contact segment224 of the auxiliary control drum 133 and 'thence through the offactuating coil.

The period of energization of the off coil 1s sufiiclent to effect themovement of the control device 131 to its position d, whereupon thecircuit of the actuating coil off is interrupted in the usual manner.

As the main control drum 132 is actuated toward its position d, theengagement of the control finger 232 with contact segment 189 is broken,thereby temporarily re-inserting 18 0 from the conductor 201 throughcontrol.

fingers 238 and 239 which are bridged by contact segment 240 andconductor 241 to the negatively energized conductor 217, whereby thelower-voltage terminal of the machine having the armature A1 is directlyconnected through the control drum to the lower-voltage terminal of theother machine having the armature A2. Thus the two motors are connectedin initial parallel relation, with the resistor R connected in commonseriescircuit relation with the motors by reason of the rengagement ofthe control finger 188 with the contact segment 189.

Actuation of the master controller to its successive remaining positions25 and u effects a step-by-step movement of the control device 131through its positions 6 and f, respectively, whereby the sections of themaincircuit resistor R are again successively short-circuited and themotors are connected in full parallel relation.

Assuming that the actuating mechanism 134 and control device 131 occupythe respective positions that are illustrated in Fig. 3, the operationthereof to effect reversed runnlng of the motors may be set forth asfollows: The two-position switching device 160 is first actuated to itsposition 7* Whereupon a circuit is completed from the trolley throughconductor 165, auxiliary resistor 162, conductor 249, control fingers250- and 251, which are bridged by contact segment 252 of the switchingdevice 160, conductor 253, control fingers 254, and 255 which are bndgedby contact segment 2560f the auxillary control drum 133, conductor 257,the actuatmg coil of the locking device 135, and conductor 258 to thenegative conductor Ground.

A further circuit is completed at this time from thecontrol finger 250of the two-positlon switching device through conductor 259, controlfingers 260 and 261 which are brldgedby contact segment 262, conductor263, 1nterlock 135in of the locking device, conductor 264, where thecircuit divides, one branch including conductor 265, interlock LS-out,the actuating coil On and conductor 184 to the negative conductorGround, and the other branch including conductor 266, interlock LSout,the actuating coil Oif,-and conductor 227, to the negative conductorGround. A circuit through bothactuating coils On and Off being thuscompleted, the control device 131 is actuated to its position a, whereinthe circuit of the actuating coil of the locking device 135 isinterrupted by the disengagement of control finger 25-4 and contactsegment 256, whereupon the temporarily raised pin 150 of the lockingdevice is again lowered in the cylinder aperture 142, and the actuatingmechanism 134 occupies the relative position that is shown in Fig. 6, aspreviously described.

The circuits of the actuating coils On and Off are also broken, upon thedeenergizationof the actuating coil of the locking device, by reason ofthe exclusion from their energizing circuit of the interlock 135in. Thusthe control device 131 is held in its initial reversed position a.

Upon actuation of the master controller to its initial operativeposition p, the circuit of the control resistor 161is completed asbefore, as is also the circuit ofthe actuating coil of the switch LSwith the exceptionthat a contact member 267 that is located in positiona. of the auxiliary control drum 133, is substituted for thepreviously-mentioned contact member 177 that engages the control fingers175 and 176 in position a.

' Subsequent movement of the master controller through its remainingpositions effects a step-by-step actuation of the control device 131through its successive reversed positionb to f, inclusive, suchoperation of the auxiliary control drum 133 and of the main control drum132 being similar to the previously described operation with theexception that ,the contact segments of the main control drum thatcorrespond to the above-described contact segments 195 and 206, and 210and 215, are interconnectedv in a well-known manner to effect a reversedconnection of the field windings F1 and F2 with respect to thecorresponding arma tures, whereby reversed operation of the motorsoccurs. Since such operation is familiar to those skilled in the art, nofurther description thereof is believed to be necessary.

Upon the return movement of the master controller to its off position,the main controlling device 131 returns as far as its initial reversedposition a, being held in that position by reason of the presence of thepin 150 of the locking device 135, as illustrated in Fig. 6. Thus, themain' control drum 132 is in position to effect immediate successivereversed operations of the motors, as will be desirable when the motorsarenecessarily reversed during the remay be actuated to its position f",whereby a circuit is completed from the positively energized controlfinger 250 through contact member 268, control finger 269, conductor270, control fingers 271 and 255, which are bridged by contact segment256 of the auxiliary control drum, and thence through the actuating coilof the locking device 135, as

previously traced. The pin 150 is thus temporarily raised within thecylinder aperture 14:2 to allow the passage of the piston 140 beyond theaperture and finally to the position that is illustrated in Fig. 3. 'Thelockin device 135 again resumes its normal position, when the maincontrol device 131 reaches its position f,by reason of the disengagementof the control finger 271 from the contact segment 2-56 of the auxiliarycontrol drum. v

We do not wish to be restricted to the specific'structural. details orarrangement of parts herein set forth, as various modifications thereofmay be elfected without departing from the spirit and scope of ourinvention. We desire, therefore, that only such limitations shall beimposed as are indicated in the appended claims.

We claim as our invention:

1. In a controller, the combination with a movable member havingindependent operpiston device to actuate it through difierent parts ofits range of travel that correspond to said operating portions.

3. The combination with a movable member having independent operatingportions, of actuating means comprising a piston device normallyoccupying a predetermined position, valve members for controlling theadmission of fluid-pressure to opposite sides of said piston device, adevice for locking Said member in a position between said portions, anactuating coil for each of said valvemembers and for said device, andmeans for selectively governing said coils to produce movement of saidpiston device through different parts of 1ts range of travel thatcorrespond to said operating portions.

' 4. In a controller, the combination with a control drum havingindependent portions corresponding to Forward and Reverse operation, ofactuating means biased toward a predetermined position and havingdifferent parts of its range of travel corresponding to said controldrum portions, and means for locking the drum in a position between saidpdrtions.

. 5. The combination with an electric motor, and a control drum havingindependent portions for completely governing forward and reverseoperation of said motor, of actuating means for the control drumcomprising a piston device normally biased toward a predeterminedposition, valvemembers for controlling the admission of fluid-pressureto opposite sides of said piston device, a device for locking said drumin a position .intermediate said portions, an actuating coil for each ofsaid valve members and for said device, and means for selectivelygoverning said coils to produce movement of said piston device throughdifierent parts of its ran e of travel that correspond I to said controldrum portions.

6. The combination with a member to be moved in the one or the otherdirection from an intermediate position, of electricallycontrolledactuating means therefor normally biased toward predetermined positions,a two-position switching device, and means for governing saidelectrically-controlled means to utilize or reverse the biasing effectin accordance with the position of said switching device.

7. The combination with a member to be moved in the one or the otherdirection from an intermediate position, of electrically-controlledactuating means therefor pneumatically biased toward predetermined"positions, a two-position switching device,

and means for governing said electrically controlled means to utllize orreverse. the

pneumatic biasing effect in accordance With the position ofsaidswitching device.

8. The combination with a member to be moved in the one or the otherdirection from an intermediate position, actuating means thereforcomprising a piston member, operating cylinders there-for, a normallyopen and a normally closed fiuid-pressure-controlling valvemember'associated with the respective ends of said cylinders to biassaid piston member toward a predetermined position, means for normallyarresting the biasing movement in an intermediate position, and meansfor relatively manipulating said valve members and said arresting meansto efl'ectmovem'ent of the movable member in the selected direction fromits intermediate position.

9. The combination with a member to be moved in the one or the otherdirection from an intermediate position, of actuating means -thereforcomprising'a piston member, operating cylinders therefor, a normallyopen and'a normally closed fiuid-pressure-controlling valve memberassociated with the outer operating cylinder therefor, a normally openand a normally closed fluid-pressurecontrolling valve member associatedwith the respective ends of said cylinder to normally bias said pistonmember toward one extreme position, a locking device for preventing theoperation of said piston member under predetermined conditions, andmeans for relatively manipulating said valve members and said lockingdevice to effect movement of the control drum in accordance with theselected operation thereof.

11. The combination with a control drum having independent portionscorresponding to different operations, of actuating means thereforcomprising a piston member, an operating cylinder therefor, a normallyopen and a normally closed fluid-pressurecontrolling valve memberassociated with the respective ends of said cylinder to normally biassaid piston member toward one extreme position, anelectrically-controlled locking device for preventing the operation ofsaid piston member under predetermined conditions, actuating coils forsaid valve members, and means for relatively energizing said coils andsaid electrically-controlled locking device to efiect a step-by-stepmove- [and] Correction in Letters Patent No. 1,330,557.

ment of the control drum through the selected operating portion thereof.

12. The combination with a movable member having independent operatingportions, of actuating means biased toward a predetermined position and.having different parts of its range of travel corresponding to saidoperating portions, and means independent of the biasing means fornormally positively maintaining said actuating means in one position.

13. The combination with a control drum having independent portionscorresponding to forward and reverse operation, of step-by-stepactuating means having different parts of its range of travelcorresponding to said control. drum portions, and means operative in thesame direction to control said actuating means during both the forablein several directions, of means for biasing said member in one directiononly to produce the selected movment, and difi'erent means forintermittently overcoming the force of said bias to interruptsaidmovement.

15. An operating mechanism comprising a piston device, a normally openvalve for admitting fluid to said iston device, a normally closed valvefor exhausting fluid from said piston device, electric circuitsincluding actuating coils for said valves, said coils being adapted tobe energized to reverse the operation of said valves, means forintennittently actuating one of said coils, and means for rearrangingsaid circuit so as-to cause the intermittent actuation of said othercoil.

In testimony whereof, we have hereunto subscribed our names this 7th dayof Sept., 1916.

KARL A. SIMMON. SAMUEL B. SCHENCK.

It is hereby certified that .in 'LettersPatent No. 1,330,557, grantedFebruary 10, 1920, upon the application of Karl A. Simmon, of EdgewoodPark, and Samuel B. Schenck, of Wilkinsburg, Penn sylvania,for animprovement in Systems of Control, an error appears the printedspecification requiring correction as follows: Page 8, lines 43-44,claim 2, strilre out the words independent of the biasing' means; andthat the said Letters Patent should be read with correction therein thatthe .same may conform to the record of the case in the Patent Ofiiee.

Signed and sealed this 16th day of March, A. D., 1920. I.

' M. H. COULSTON, v Acting Uommiesionuqf Patents.

